0.00037 = 3.7×10^-4
37,000 = 3.7×10^4
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The exponent of 10 is the place-value multiplier that the most-significant digit has.
In the first number, the most-significant digit (3) is multiplied by 0.0001 to find its place value. Of course 0.0001 = 10^-4.
In the second number, the most significant digit (3) is multiplied by 10,000 to find its place value. You know that 10,000 = 10^4.
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and the solutions are decreasing functions.